Tag: Immunohistochemistry

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Glioma Spheroids Obtained via Ultrasonic Aspiration Are Viable and Express Stem Cell Markers

Glioma, Immunohistochemistry, Organotypic, Spheroids, Tumor-initiating cells, Ultrasonic aspiration

Neurosurgery 73:868–886, 2013

Ultrasonic aspirators allow safe, rapid, and accurate removal of brain tumors. However, the tissue fragments removed are used surprisingly little in research.

OBJECTIVE: To investigate whether such tissue fragments could be cultured as organotypic multicellular spheroids because access to biopsy tissue is often limited.

METHODS: Tissue fragments obtained by ultrasonic aspiration from 10 glioblastomas and tumor biopsy tissue from 7 of these tumors were cultured in serum-containing and serum-free medium. On culturing, the fragments formed spheroids, which were prepared for histology. Two glioblastoma cell lines from ultrasonic fragments and biopsy tissue were established as well.

RESULTS: Hematoxylin and eosin staining showed viable glioma spheroids obtained from both ultrasonic and biopsy tissue in both types of medium. Endothelial growth factor receptor and PTEN/chromosome 10 status was found to be preserved in most spheroids (7-8 of 10 tumors), together with the level of glial fibrillary acidic protein, von Willebrand factor, and Ki-67. The levels of stem cell markers CD133, Bmi-1, nestin, and Sox2 also were preserved. The ultrasonic spheroids had higher levels of glial fibrillary acidic protein and von Willebrand factor and lower levels of Bmi-1, nestin, Sox2, and Olig2 compared with conventional biopsy spheroids. For both types of spheroids, the stem cell medium seemed to favor expression of stem cell markers. The established cell lines were capable of both spheroid formation at clonal density and tumor formation in vivo.

CONCLUSION: Viable organotypic and proliferating spheroids were easily obtained from ultrasonic tissue fragments. The preservation of markers and the establishment of cell lines with tumor-initiating cell properties suggest ultrasonic spheroids as a new tissue resource for glioma research.

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ELTD1, a Potential New Biomarker for Gliomas

ELTD1, a Potential New Biomarker for Gliomas

Neurosurgery 72:77–91, 2013

Glioblastoma multiforme (GBM), a high-grade glioma, is characterized by being diffuse, invasive, and highly angiogenic and has a very poor prognosis. Identification of new biomarkers could help in the further diagnosis of GBM.

OBJECTIVE: To identify ELTD1 (epidermal growth factor, latrophilin, and 7 transmembrane domain-containing protein 1 on chromosome 1) as a putative gliomaassociated marker via a bioinformatic method.

METHODS: We used advanced data mining and a novel bioinformatics method to predict ELTD1 as a potential novel biomarker that is associated with gliomas. Validation was done with immunohistochemistry, which was used to detect levels of ELTD1 in human high-grade gliomas and rat F98 glioma tumors. In vivo levels of ELTD1 in rat F98 gliomas were assessed using molecular magnetic resonance imaging.

RESULTS: ELTD1 was found to be significantly higher (P = .03) in high-grade gliomas (50 patients) compared with low-grade gliomas (21 patients) and compared well with traditional immunohistochemistry markers including vascular endothelial growth factor, glucose transporter 1, carbonic anhydrase IX, and hypoxia-inducible factor 1a. ELTD1 gene expression indicates an association with grade, survival across grade, and an increase in the mesenchymal subtype. Significantly high (P , .001) in vivo levels of ELTD1 were additionally found in F98 tumors compared with normal brain tissue.

CONCLUSION: Results of this study strongly suggests that associative analysis was able to accurately identify ELTD1 as a putative glioma-associated biomarker. The detection of ELTD1 was also validated in both rodent and human gliomas and may serve as an additional biomarker for gliomas in preclinical and clinical diagnosis of gliomas.

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Vascular Endothelial Growth Factor: The Major Factor for Tumor Neovascularization and Edema Formation in Meningioma Patients

Neurosurgery 67:1703–1708, 2010 DOI: 10.1227/NEU.0b013e3181fb801b

Peritumoral brain edema (PTBE) may be crucial in the clinical outcome of meningioma patients. The underlying pathogenetic key mechanism has so far not been determined. Sex, age, tumor size, location, involvement of other structures, or the histological appearance was not found to sufficiently explain PTBE formation in meningiomas.

OBJECTIVE: As PTBE formation is widely accepted to be vasogenic, we investigated the role of vascular endothelial growth factor (VEGF) and pial supplying vessels in a series of World Health Organization (WHO) grade I meningiomas.

METHODS: A total of 79 patients with WHO grade I meningiomas were immunohistochemically studied for VEGF and MIB-1. Pre- and postoperative magnetic resonance imaging including 3-dimensional reconstruction of 1.3-mm thick layers, with calculation of tumor and edema volume, was performed. Intraoperatively, the vascular supply and arachnoidal state were noted by the neurosurgeon.

RESULTS: VEGF was found to be exclusively confined to meningioma tumor cells. We identified 4 different patterns. VEGF and supplying pial vessels were found in 14 meningioma patients, pial vascular supply only in 3, VEGF expression only in 46, and neither VEGF expression nor supplying pial vessels in 16. Only the occurrence of both pial vascular supply and tumor VEGF expression was found to be correlated with PTBE formation (P , .002).

CONCLUSION: Our data suggest that VEGF may be crucial in angiogenesis and therefore indirectly in PTBE formation in World Health Organization grade I meningiomas

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